Surface: Add allocateBuffers to avoid render delay

This plumbs up a new call on the native Surface object that allows
the client to request that BufferQueue pre-allocate all of the buffers
that it might need for rendering. This hopefully prevents allocation
delays during dequeuing and reduces jank.

Bug: 11792166
Change-Id: Ibeaa7475492d4ac2bcacb107ef60c6240081d8b7

1 files changed, 13 insertions, 0 deletions

diff --git a/core/java/android/view/Surface.java b/core/java/android/view/Surface.java
index fdaae01..78986d9 100644
--- a/core/java/android/view/Surface.java
+++ b/core/java/android/view/Surface.java
@@ -51,6 +51,8 @@ public class Surface implements Parcelable {
     private static native long nativeReadFromParcel(long nativeObject, Parcel source);
     private static native void nativeWriteToParcel(long nativeObject, Parcel dest);
 
+    private static native void nativeAllocateBuffers(long nativeObject);
+
     public static final Parcelable.Creator<Surface> CREATOR =
             new Parcelable.Creator<Surface>() {
         @Override
@@ -420,6 +422,17 @@ public class Surface implements Parcelable {
     }
 
     /**
+     * Allocate buffers ahead of time to avoid allocation delays during rendering
+     * @hide
+     */
+    public void allocateBuffers() {
+        synchronized (mLock) {
+            checkNotReleasedLocked();
+            nativeAllocateBuffers(mNativeObject);
+        }
+    }
+
+    /**
      * Exception thrown when a Canvas couldn't be locked with {@link Surface#lockCanvas}, or
      * when a SurfaceTexture could not successfully be allocated.
      */